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64 Wednesday Oct. 11th [[squiggly vertical line] attaching to the discharging rod a needle so as to make the transfer by degrees, the needle was magnetized in the opposite direction, or so as to indicate an ascending current towards the [[underline]] plus [[/underline]] side of the plate. [[Diagram in margin is glass plate with electrical wand passing over the plate, with wire dropping down. Wire is shown with resistor and arrow pointing up along the wire. Plate is turned at an angle so that the wand indicates one ball on one side of the glass and the other ball on the other side.]] Repeated the above experiment with the different side of the glass, and found that in all cases when the discharge was made either rapid or slow, the needle on the negative side was [[strikethrough]] [[?]] [[/strikethrough]] magnetized by a descending current, while that in connection with the plus side of the glass with a sudden discharge was downwards, while with a slow discharge, upwards The discharge was upwards or towards the positive side of the glass, even when a spark passed between the needle point and the tinfoil of the glass. I found it is not invariably the case that a slow discharge gives a current downwards from the [[underline]] minus [[/underline]] side of the glass. Sometimes the result is different, but this may result from the spark drawn first by touching the side. The change of the direction in the above experiments depend principally on the extra spark being drawn from one or other side, but all the experiments I have thus far made, indicate that a sudden discharge of the glass plate sends a current from the plate from both sides to the ground. [[end page]] [[start page]] Wednesday Oct 11th 1843 √ 65 Made an experiment of the haphazard kind on the fringes produced by light. Sent charge from jar through two wires, which formed the apparatus of the two openings in diffraction, but no effect could be observed - The apparatus was formed by connecting a wire, as in the figure, on the surface of a piece of mica, and then two ends of this brought into contact with the opposite sides of a charged jar. The experiment must also be tried with galvanic electricity - The wires pass in opposite direction and may on this account vary the result, since the induced currents may neutralize each other. [[Drawing to the left of the above paragraph of the glass pane with connecting wire and plus sign top left and bottom right]] Arrange the discharges, as in the [[anexed?]] figure, first took the induction from [[underline]] a [[/underline]], and then from [[underline]] b [[/underline]], on each side of the break. The result however was the same, the needle was magnetized by a [[descending]] current in each case. [[Illustration of the experiment described above to the left of the text]] See Priestley on lateral discharge. Made an arrangement of wire similar to that represented in the figure, connected one end with the machine [[underline]] a [[/underline]] [[underline]] b [[/underline]] -, parallel to this I placed a wire [[underline]] e [[/underline]] f, which was joined at its two ends at g, when the machine was turned so as to charge, [[underline]] h [[/underline]] [[underline]] i [[/underline]], and then the electricity drawn off at [[underline]] a [[/underline]], a current was produced in [[underline]] e [[/underline]] [[underline]] f [[/underline]]. The [[side?]] in the spiral no 1 gave a current -, those in no 2 and 3 gave a current +.
